feat: add process discovery tests

Author: dmehala

manifests/dotnet.yml

@@ -449,6 +449,7 @@ tests/:
       Test_Parametric_OtelSpan_Set_Name: bug (APMAPI-778) # updates the operation name of the span not the resource name
       Test_Parametric_Otel_Baggage: incomplete_test_app (otel baggage endpoints are not implemented)
       Test_Parametric_Otel_Current_Span: incomplete_test_app (otel current span endpoint are not implemented)
+    test_process_directory.py: missing_feature
     test_span_events.py: missing_feature
     test_span_links.py: missing_feature
     test_telemetry.py:

manifests/golang.yml

@@ -568,6 +568,7 @@ tests/:
       Test_Otel_Env_Vars: v1.66.0
     test_otel_span_with_baggage.py:
       Test_Otel_Span_With_Baggage: missing_feature
+    test_process_directory.py: missing_feature
     test_parametric_endpoints.py:
       Test_Parametric_DDSpan_Add_Link: missing_feature (add_link endpoint is not implemented)
       Test_Parametric_DDSpan_Set_Resource: missing_feature (does not support setting a resource name after span creation)

manifests/java.yml

@@ -1609,6 +1609,7 @@ tests/:
         '*': incomplete_test_app (endpoint not implemented)
         spring-boot: v1.39.0
   parametric/:
+    test_process_directory.py: missing_feature
     test_config_consistency.py:
       Test_Config_Dogstatsd: missing_feature (default hostname is inconsistent)
       Test_Config_RateLimit: v1.41.1

manifests/nodejs.yml

@@ -799,6 +799,7 @@ tests/:
         express4: *ref_5_26_0
         express5: *ref_5_26_0
   parametric/:
+    test_process_directory.py: missing_feature
     test_128_bit_traceids.py:
       Test_128_Bit_Traceids: *ref_3_0_0
     test_config_consistency.py:

manifests/php.yml

@@ -386,6 +386,7 @@ tests/:
     test_context_propagation.py:
       Test_Otel_Context_Propagation_Default_Propagator_Api: incomplete_test_app (endpoint not implemented)
   parametric/:
+    test_process_directory.py: missing_feature
     test_128_bit_traceids.py:
       Test_128_Bit_Traceids: v0.84.0
     test_config_consistency.py:

manifests/python.yml

@@ -771,6 +771,7 @@ tests/:
         '*': incomplete_test_app (endpoint not implemented)
         flask-poc: v2.19.0
   parametric/:
+    test_process_directory.py: missing_feature
     test_128_bit_traceids.py:
       Test_128_Bit_Traceids: v2.6.0
     test_config_consistency.py:

manifests/ruby.yml

@@ -411,6 +411,7 @@ tests/:
         '*': incomplete_test_app (endpoint not implemented)
         rails70: v2.0.0
   parametric/:
+    test_process_directory.py: missing_feature
     test_config_consistency.py:
       Test_Config_Dogstatsd: missing_feature
       Test_Config_RateLimit: v2.0.0

tests/parametric/test_process_discovery.py

@@ -0,0 +1,74 @@
+"""
+Test the instrumented process discovery mechanism feature.
+"""
+
+import pytest
+import json
+import msgpack
+from jsonschema import validate as validation_jsonschema
+from utils import features, scenarios
+
+
+def find_dd_memfds(test_library, pid: int) -> list[str]:
+    _, out = test_library.container_exec_run(f"find /proc/{pid}/fd -lname '/memfd:datadog-tracer-info*'")
+    if not out:
+        return []
+
+    memfds = out.split()
+    return memfds
+
+
+def validate_schema(input: str) -> bool:
+    schema = None
+    with open("utils/interfaces/schemas/library/process-discovery.json", "r") as f:
+        schema = json.load(f)
+
+    try:
+        validation_jsonschema(input, schema)
+        return True
+    except Exception:
+        return False
+
+
+def read_memfd(test_library, memfd_path: str):
+    rc, output = test_library.container_exec_run_raw(f"cat {memfd_path}")
+    if rc != 0:
+        return rc, output
+
+    return rc, msgpack.unpackb(output)
+
+
+@scenarios.parametric
+@features.process_discovery
+class Test_ProcessDiscovery:
+    @pytest.mark.parametrize(
+        "library_env",
+        [
+            {"DD_SERVICE": "a", "DD_ENV": "test", "DD_VERSION": "0.1.0"},
+            {"DD_SERVICE": "b", "DD_ENV": "second-test", "DD_VERSION": "0.2.0"},
+        ],
+    )
+    def test_metadata_content(self, test_library, library_env):
+        """
+        Verify the content of the memfd file matches the expected metadata format and structure
+        """
+        with test_library:
+            # NOTE(@dmehala): the server is started on container is always pid 1.
+            # That's a strong assumption :hehe:
+            # Maybe we should use `pidof pidof parametric-http-server` instead.
+            memfds = find_dd_memfds(test_library, 1)
+            assert len(memfds) == 1
+
+            rc, tracer_metadata = read_memfd(test_library, memfds[0])
+            assert rc == 0
+            assert validate_schema(tracer_metadata) == True
+
+            assert tracer_metadata["schema_version"] == 1
+            assert tracer_metadata["runtime_id"]
+            # assert tracer_metadata["hostname"]
+            # TODO(@dmehala): how to get the version?
+            # assert tracer_metadata["tracer_version"] ==
+            assert tracer_metadata["tracer_language"] == test_library.lang
+            assert tracer_metadata["service_name"] == library_env["DD_SERVICE"]
+            assert tracer_metadata["service_version"] == library_env["DD_VERSION"]
+            assert tracer_metadata["service_env"] == library_env["DD_ENV"]

utils/_features.py

@@ -1724,7 +1724,9 @@ def semantic_core_validations(test_object):
         return test_object
 
     @staticmethod
-    def aws_sqs_span_creationcontext_propagation_via_xray_header_with_dd_trace(test_object):
+    def aws_sqs_span_creationcontext_propagation_via_xray_header_with_dd_trace(
+        test_object,
+    ):
         """[AWS-SQS][Span Creation][Context Propagation][AWS X-Ray] with dd-trace
 
         https://feature-parity.us1.prod.dog/#/?feature=263
@@ -1733,7 +1735,9 @@ def aws_sqs_span_creationcontext_propagation_via_xray_header_with_dd_trace(test_
         return test_object
 
     @staticmethod
-    def aws_sqs_span_creationcontext_propagation_via_message_attributes_with_dd_trace(test_object):
+    def aws_sqs_span_creationcontext_propagation_via_message_attributes_with_dd_trace(
+        test_object,
+    ):
         """[AWS-SQS][Span Creation][Context Propagation][AWS Message Attributes] with dd-trace
 
         https://feature-parity.us1.prod.dog/#/?feature=264
@@ -1796,7 +1800,9 @@ def rabbitmq_span_creationcontext_propagation_with_dd_trace(test_object):
         return test_object
 
     @staticmethod
-    def aws_sns_span_creationcontext_propagation_via_message_attributes_with_dd_trace(test_object):
+    def aws_sns_span_creationcontext_propagation_via_message_attributes_with_dd_trace(
+        test_object,
+    ):
         """[AWS-SNS][Span Creation][Context Propagation] with dd-trace
 
         https://feature-parity.us1.prod.dog/#/?feature=271
@@ -1850,7 +1856,9 @@ def host_block_list(test_object):
         return test_object
 
     @staticmethod
-    def aws_kinesis_span_creationcontext_propagation_via_message_attributes_with_dd_trace(test_object):
+    def aws_kinesis_span_creationcontext_propagation_via_message_attributes_with_dd_trace(
+        test_object,
+    ):
         """[AWS-Kinesis][Span Creation][Context Propagation] with dd-trace
 
         https://feature-parity.us1.prod.dog/#/?feature=280
@@ -2390,5 +2398,15 @@ def otel_propagators_api(test_object):
         pytest.mark.features(feature_id=361)(test_object)
         return test_object
 
+    @staticmethod
+    def process_discovery(test_object):
+        """Process Disocvery
+
+        https://feature-parity.us1.prod.dog/#/?feature=362
+        RFC: <https://docs.google.com/document/d/1kcW6BLdYxXeTSUz31cBqoqfW1Jjs0IDljfKeUfIRQp4/edit?tab=t.0>
+        """
+        pytest.mark.features(feature_id=362)(test_object)
+        return test_object
+
 
 features = _Features()

utils/interfaces/schemas/library/process-discovery.json

@@ -0,0 +1,49 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "/library/process-discovery.json",
+  "title": "Tracer Metadata",
+  "description": "Metadata format used for process discovery",
+  "type": "object",
+  "properties": {
+    "schema_version": {
+      "type": "integer",
+      "description": "Version of the schema"
+    },
+    "runtime_id": {
+      "type": "string",
+      "description": "Runtime UUID"
+    },
+    "tracer_version": {
+      "type": "string",
+      "description": "Version of the Datadog tracer library"
+    },
+    "tracer_language": {
+      "type": "string",
+      "description": "Programming language of the tracer library"
+    },
+    "hostname": {
+      "type": "string",
+      "description": "An identifier for the machine running the process"
+    },
+    "service_name": {
+      "type": "string",
+      "description": "Name of the service being instrumented"
+    },
+    "service_env": {
+      "type": "string",
+      "description": "Environment of the service being instrumented"
+    },
+    "service_version": {
+      "type": "string",
+      "description": "Version of the service being instrumented"
+    }
+  },
+  "required": [
+    "schema_version", 
+    "tracer_version",
+    "tracer_language",
+    "hostname"
+  ]
+}
+
+